Good advise above from itdo2^^^^
Where is this East Liverpool? In the UK or some place in the USA that I would never know about.
If in the UK is this an Export CRD?
Check the battery connectors, the negative battery lead going to chassis and the engine grounding leads grounding engine to chassis are clean and tight.
Check the thick lead on the alternator is on tight...disconnect battery first as this point is always live! Also re-plug the small connector on the alternator.
With battery disconnected....re-plug the connectors on the PCM a few times to clean the contacts.
When I had charging issues on my 2002 Export CRD I plugged my Multi meter into the front cigar/power points so that I could monitor the voltage while driving.....I had multiple wiring issues!
Also the early KJs have a Battery Temperature Sensor located under the battery which informs the PCM how hot it is and the PCM then slightly adjusts the voltage on the alternator to compensate. If there is a problem with this sensor then it sets the same battery Icon on the cluster as a charging problem would but I doubt that this is your issue as a failing temperature sensor has little effect on the final charging and would not affect the headbeams etc.
You will need to look at the wiring diagram to trace the wiring to look out for cables fraying to engine/chassis and check if you suddenly get these faults coming up when you do some action...I had problems when I turned on the front wipers or turned on the aircon for example.
Download the 2003 KJ Service Manual here...includes wiring diagrams.
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